Machine for shaping plastic materials



Jan. 5, 1943.

J. DICHTER MACHINE FOR SHAPING PLASTIC MATERIALS I Filed Sept. 9, 1940 3Sheets-$heet l 4: wNN W O.

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Jan. 5, 1943. .1. DICHTER MACHINE FOR SHAPING PLASTIC MATERIALS FiledSept. 9, 1940 3 Sheets-Sheet 2 NNN Jaifob Di 2 2; @4114, 6.

Jan. 5, 1943. J, DI Q 'Q 2,307,114

MACHINE FOR SHAPING PLASTIC MATERIALS Filed Sept. 9, 1940 3 Sheets-Sheet3 Patented Jan. 5, 1943 Jakob Dichter, Berlln-S choneberg, GermanyApplication September 93 1940, Serial No. 358,092 Germanyseptember 13,1939 V 2 Claims. (CI. 18-19) 3 The present invention pertains to theshaping of bodies formed from plastic materials such as celluloseacetate; More particularly the invention relates to the reshaping ofhollow cylindrical bodies produced by dipping, drawing, or other wellknown methods. In certain types of plastic material containers, forinstance, cylinders are formed by dipping a cylindrical mold in thepies. tic material which is then permitted to dry and assume the shapeof the mold. Usually the mold has a semi-spherical end, the body formedthereon consequently having a rounded bottom. After the container isdried, it is cut to a suitable length and further shaped, if desired.

One of the objects of this invention is to provide an improved machineincluding conveying mechanism and shaping devices which automaticallyreshape preformed bodies of the character referred to.

Another object of the invention is the provision of novel mechanism foraccurately presenting the bodies to shaping dies and the operation ofsaid mechanism in timed relation to the actuation of the dies. 7

Other objects will be apparent from the following description of themachine in which reference is made to the drawings illustrating oneembodiment 'of the invention. In the drawings:

Fig. 1 is a sectional side elevationof the machine;

Fig. 2 is a top plan view of the machine shown in Fig. 1;

Fig. 3 is a front view, partly'in section, ofthe machine;

Fig. 4 is a fragmentary plan view of the transporting chain; and Fig. 5is an enlarged fragmentary section of a molding plug employed in themachine.

Referring to the, drawings, it will be seen that the base of the machinecomprises side frames l,-

I connected by tie-rods 2,'the side frames supporting bearings 3 inwhich cam shaft 4 is journaled. Keyed to shaft 4 is a worm gear 5, thelatter being driven by worm 8 on shaft 8. Bear-- ings l, 'l' accommodateshaft 8 which is rotated by a suitable motor (not shown).

The conveyor is adapted to be guided by the endless channel-shaped guiderails 9, 9' attached at opposite sides of the machine to members III, IIof the side frame. This conveyor comprises mounted on pins l1, l1 andadapted to carry the chains over the guide rails. 9,9 and the curvedportions I8, l8 thereof. It will be seen from Fig. 4 that each link ofthe conveyor chain is apertured at 2| to receive a container, theapertures being of sufficient diameter to accommodate the largest sizecontainer to be shaped. Suitable bushings 22 are provided to be insertedin openings 2| and adapted to accommodate containers of smallerdiameter.

The containers, indicated at 23, are deposited at the forward end of themachine in the openings of the conveyor links either manually or byautomatic means, the latter forming no part of this invention andtherefore not being shown. Thereafter the conveyor is given astep-by-step movement by the following mechanism. Bevel gear 24 fast onshaft 4 meshes with bevel gear 24' secured to shaft 28,, to the latterof which is keyed cam 25. Pivoted to the side frame at 21 is a lever 28having a cam follower 29 thereon, the follower engaging cam 25. Aconnecting link 30 is pivotally connected at its ends to the free endsof lever 28 and arm 3| fast on shaft 32 to which are also secured arms33, 33'. Pivotally connected to the ends of arms 33, 33' are pawlmerfibers 34, 34, having hooked ends which are adapted to engage rollersl9, l9 during their downward travel, to index the chain forwardly alimited distance, equal to the distance between the shaping stations ofthe machine. As will be seen in Fig. 2, the upper flanges of thechannel-shaped guide rails 9, 9' are recessed at 35 to permit the pawlsto engage the rollers. I

Lever 28 and arm 3| are normally urged toward the right in Fig. 1 byspring 38, thus maintaining engagement of follower 29 with cam 25.Positioned at opposite sides of the conveyor are arcuate arms 31, 31'keyed to shaft 38" and acting as guides for rollers 38, 38' on pawls 34,34'.

Arm 39, also fast on shaft 38", is oscillated by cam 40 on shaft 4. Onthe return upward of the pawls, arms 31, 31 are swung away from theconveyor, thus holding the pawls out'of engagement with rollers l9, l9.

To prevent overtravel of the chain and accurate positioning thereof withrespect to the shaping devices, a stop arm .4! having a V-s'haped aplurality of supporting links 13 having bearings l4, l4 formed thereonand other'similar links II provided with bearings l8, l8, the linksbeing connected by pins l1, l1 passing through bearings l4, l4, l8, l6.Rollers l9, I! are rotatably projection 48 is secured to shaft 44 towhich is also fastened arm 43, shaft 44 being rotatably mounted inbearing 42. Arm 4| is connected by means of link 45 to lever 46 pivotedto the frame I and oscillated by cam 41 to rock into and out ofengagement with roller I 9 in timed relation to movement of theconveyor, 1. e"., projection 48 engages successive rollers at the end ofeach forward advance accurately to position the conveyor during theshaping operation.

In Figs. 1 and 3 it will be seen that the bottoms of the containers 23ride on rails 49 supported on frame 59 each of the rails being aperturedat points corresponding to processing stations I, II, In and IV. At twoof the stations push rods 50 are aligned with certain of these aperturesand are adapted to be reciprocated to elevate the containers. Push rods50 are adjustably fixed to plate mounted on slides 56,56 to which aresecured racks 51, 51'. Connecting rod 52 is pivotally attached to crank53 on shaft 54 to which are keyed gears 55, 55' meshing with the rack.Suitable cam means (not shown) reciprocates rod 52 which, through themechanism just described, lowers and elevates plate 5| and push rods 50.In a similar manner shaping tool 58 is reciprocated by crank 60, gearSI, and racks 82.

On each side of the machine are plates or uprights 53 for supporting theshaping tools and their operating mechanisms. If it is desired to formthreads on the open ends of the containers, the following apparatus isemployed. Cross-member 64 carries on the under side thereof a guideplate 68 in which are slidably supported a pair of opposed threadingdies 65, 65, each of which is heated anddesigned to thread half of thethread circumference. Plunger 66 guided in cross-member 64 carries atits lower end a slightly conical rubber sleeve 61, the upper end ofwhich is somewhat larger than the bore guiding plunger 66 and adapted toabut guide plate 68 so that, when plunger 66 is elevated, the rubberring will expand. The means for elevating plunger 66 consists ofbell-crank 69 oscillated by cam 1| on shaft to which is secured arm I2.The latter is connected to lever 14 by means of link 13. Cam I5 rockslever 14 and, consequently, bell-crank 59. It will be seen that plunger66 is connected to the bell-crank by a turnbuckle I6 adjustment whereofmay be made by turning a toothed pin I8 meshing with a toothed portionI9 of the turnbuckle and supported in bracket 11, the latter formingpart of the pivotal connection between bell-crank 69 and the turnbuckle.

The threading jaws are reciprocated in opposite directions by means of acam 84 keyed to shaft 84' and actuated by cam 80 on shaft 4 throughlever 8|, link 82, and arm 83, also fixed to shaft 84'. Cam 84 actsdirectly on die 65 and indirectly on die 05' through levers 85, 88,connected by link 81, the length of which may be varied by adjustment ofturnbuckle 86.

At station 11 there is shown a die indicated at 80 designed to form areinforcing lip on the containers in the event a stopper rather than ascrew-thread cap is employed as a closure for the container. The lipforming die, which is heated, is carried by a plunger 9i mounted forvertical reciprocation in bearing 90 and is connected by link 92 to arm93 keyed to shaft 94.

Also secured to shaft 04 is an arm 05 connected to lever 90 by linkLever 00 is adapted to be rocked by cam 91 on shaft 4, thus effectingreciprocation of the lip forming die 80.

If it is desired to form containers having fiat bottoms instead of therounded bottoms produced by the clipping molds, the container may bereshaped at station 111 by the bottoming die indicated at 58 and head 00on reciprocable plunger 98'. Cross-piece 00 is slidably mounted forvertical reciprocation on uprights I00 and carries a plurality ofplungers 00'. Reciprocation of the cross-piece is effected bybell-cranks IN, IN on shaft I02 connected to lever I04 by link I03.Lever I04 is rocked by cam I05 on shaft 4.

When the container is to be perforated to provide ventilation, themechanism illustrated at station IV is employed. Die I00 is apertured tocorrespond with punches I01 on plunger I09, of which there is aplurality. These plungers are carried by cross piece I00 which isvertically reciprocated by the mechanism consisting of hellcranks H0, H0on shaft III, link II3, lever H4 and cam II2 on shaft 4.

Provisions are made to use only one or more of the several shapingtools, the connecting links between the main cams on the tools beingreadily removable. The stations are spaced a distance equal to thelength of the links and the advancing or indexing mechanism is sodesigned that the conveyor is indexed a distance equal to that betweenstations. All of the cams for advancing and elevating the work,reciprocating the tools and providing for alternate operation of theconveyor and tools are so timed that the mechanisms operate in accuratesequence.

While the drawings illustrate a preferred form of the invention, it isto be understood that the machine may be modified and is to be limitedonly by the terms of the following claims.

Having described my invention what I claim as new and desire to secureby Letters Patent is:

1. Apparatus for threading an open end of a body of plastic materialcomprising a heated threaded die, means for eflecting relative movementbetween said die and the body to bring the die into engaging relationwith the body, a plunger, elastic means on said plunger insertable inthe open end of the body, a guide for said plunger, and means for movingsaid elastic means into engagement with said guide to expand saidelastic means to force the body into said die.

2. Apparatus for threading an open end of a body of plastic materialcomprising a heated threaded die, means for effecting relative movementbetween said die and the body to bring the die into engaging relationwith the body, a plunger, a conical rubber member on said plungerinsertable in the open end of the body, a guide for said plunger, andmeans for moving said member into engagement with said guide to expandsaid elastic means to force the body into said die.

JAKOB DICHTER.

